Crankshaft grinder



H. T. RUTHERFORD Nov. 21, 1950 CRANKSHAFT GRINDER Filed Aug. 19, 1946 4 Sheets-Sheet l He: may T 9a zherforcz.

H. T. RUTHERFORD 2,531,160

CRANKSHAFT GRINDER Nov. 21, 1950 4 Sheets-Sheet 2 Filed Aug. 19, 1946 1 77 T FEuiherforcZ Nov. 21, 1950 H. T. RUTHERFORD 2,

CRANKSHAFT GRINDER 4 Sheets-Sheet 5 1 H Wm 1 v 2.7 Flg' F7U l2.

grwmvtm 1950 H. T. RUTHERFORD 2,531,160

CRANKSHAFT GRINDER 4 Sheets-Sheet 4 Filed Aug. 19, 1946 Harry TFPQZ z her/0rd.

Patented Nov. 21, 1950 CRANKSI-IAFT GRINDER Harry "1.Rutherford;'-Baltin ore, Md., assignor to Vickers, Incorporated, Detroit, Mich., a corporation of Michigan Application August 19, 1946, Serial No. 691,554

39 Claims.

[The present invention relates to a portable crank shaft grinding tool and especially to a grinding tool adapted to ire-condition the connecting rod portion; or throw, of a crank shaft.

The" improved grinder comprising the present invention is primarily adapted for use in automobile, truck, and other motor vehicle engines. Because of the compactness of the present day automobile engine'and its location in relation to the chassis, it has become practically impossible to work on these .throw portions without removing the engine from the vehicle. It is with this in mind thatthe present tool has been developed. lihe tool is so designed and constructedthat by removing the cylinderhead, piston and the connecting rod from the engine it may be inserted through the cylinder and operated within the space normally occupied-byithe piston and connecting rod.

While the grinding tool isespecially designed for englnes'of motor vehicles, the principles of the invention are applicable to other uses and the grinder may be employed on engines in general regardless of their nature. 7 The connecting 'rod receiving portion of-the crank shaft may forapurposesjof conveniencewbe designated as bearingythrow, or shaft.

Theprimary'object of the inventionis to provide a grin-ding tool of such dimensions that it may be placed in operation through'the cylinder, after the removalof the cylinder head; piston and the connecting .rod, for grinding the connecting rod receiving portionof the crank shaft withoutremoving the engine from the vehicle, or the shaft from the main engine ibearings.

. Another objcctof the inventionis to so con struct the device that the grinding wheel maybe more accurately regulated during the grinding operation. i

A further object of the invention is tov provide an improved method of grinding the surface of theconnecting rod receiving portion of the crank shaft.

Still a further object of the inventionbeing to provide a grinding-tool which is held in operatingpositionby the engine cylinder and the-corresponding connecting rod receiving portion of the crank shaft.

Other objects and advantages of theinvention not at this time more particularly enumerated will becomereadily apparent as thenature of the invention is better understood. The novel construction, combination and arrangement of parts will be clearly shown in the accompanying sheets of drawings forming a part of th specilidations in which: i

Figure 1 is an assembly view of the grinding tool together with a fragmentary view of a typical engine cylinder, illustrating the' man'ne r in which the tool is used; and its relative position in relation to the cylinder and'thecorresponding connecting rod receiving portion .of the crank shaft.

Figure 2 is a sectional view taken along the line 2-2 of Figure '1.

Figure 3 is an enlarged view in elevationof the form of grinding tool shown in Figure 1 Figure 4 is atop plan view of the same.

Figure 5 is a diagrammatic plan view of the grinding wheel and portions of 'thecrank shaft showing the'grinding' surface of the wheel rotating substantially at a tangentto the bearing surface of the shaft and to one side of the center line thereof.

Figure 6 is a view similar to Figure 5 in which the axis of the rotating grinding wheel is perpendicular with'the center line of the shaft.

Figure 7 is a view taken along the line l-l of Figure 3.

Figure 8 is a fragmentary view in elevation of the lower end of the tool looking from the right in Figure 3.

- Figure 9 is a sectional view taken along the line 99 of Figure 7.

Figure 10 me fragmentary view in elevation of a modified form of shaft supporting means.

Figure 11 is a fragmentary view in elevation of the modified .form of shaft supporting means looking from the right in Figure 10.

Figure 12 is a fragmentary sectional view taken along the line 12-42 of Figure 10.

Figure 13 is a view in elevation of a modified form of variable expansion guide 'member' for guiding-the outer end'of the tool.

Figure 14 is a topplan view of same.

Figure 15 is a sectional view taken along the line I 5l 5 of Figure 13.

Figure '16 .is an enlarged fragmentary view partly in section of the actuating arm and fastening means for the variable expansion member of the guide member.

. .In th following detailed description like numerals will designate like parts throughout the several views.

The general organization of the invention is best understood by referring first to the form shown in Figures 1 to 9. In the drawings a typical crank shaft is designated at 2 and its connecting rod receiving portion at 2. In the present form the invention comprises a crank shaft positioning means having a U-shaped frame formed by the arms 4 and .4, which are adapted 3 to extend downwardly through the cylinder and over the connecting rod receiving portion of the crank shaft. Connecting the two outer ends of the U-frame is a member 6, one end being hinged at 8 to the side member 4 of the U-frame, the other end being secured to the opposite frame member i b the pivoted threaded bolt l8 and knurled nut l 2. At the closed ehd of the U-frame and integral therewith is a hollow tube member It which is slidabl'y receivable over a tube member I6 and. is secured thereto by a set screw I8. Extending through the tube 16 is a drive shaft 28 the inner end of which is threaded and adapted to extend slightly within the end of the base of the U-frame. Threadably receivable on the threaded end of the drive shaft is a grinding wheel 22. The grinding wheel is preferably driven by a motor 24 through a conventional flexible shaft 26 extending inwardly through the cylinder which is in turn connected with the outer end of the shaft 28. The shaft 28 is provided with appropriate thrust bearings (not shown) adjacent the grinding wheel to prevent any end- .play of the shaft and to the wheel which is carried by the shaft.

The hinged member 6 carries the means by which the grinding wheel is brought in contact with the portion 2 of the shaft. Within the upper portion of the hinged member 6 there is provided a rectangular slot 28. Slidably fitting within this slot is a support 38 having at its upper surface laterally extended flange members 32 and 3d for contacting the shaft at the points 32 and 34 adjacent its lower arc. Extending down- ,wardly and centrally of the slot 28 is a threaded aperture 38 and threadably receivable within the aperture is a screw 38. The screw is provided with a knurled head 39. Secured to the frame 6 is a spring 48, the outer edge of which engages the knurled head 39 of the screw 38 for retaining the screw in adjusted positions. The base portion of member 38 is provided with an aperature 42 for receiving a reduced portion 38' of the screw member 38. A shoulder 44 is formed between the reduced portion and the threaded portion of the screw and is adapted to bear against the under surface of the base portion. of the member 38. By rotating the screw 38 within the aperture 36 the support 38 may be adjusted relative to the depth of the slot 28 of the hinge member 6 and the grinding wheel 22, which brings the grinding wheel is contact with the bearing surface. Located approximately midway between the grinding wheel and the support 38 and adapted to'contact the circumference of the shaft is a roller 25, which is carried on'an adjustable pin 21. The pin is supported within an aperture 3| in the U-shaped member 4, and is held in position by the, set screw 29.

The width of the support 38is substantially the same 'asthe width of the connecting rod bearing surface as shown in Figures 8'and v9. The flange members 32 and 34 are provided on their upper surface adjacent the outer edges with ribs 46'and 46'. These ribs are adapted to rest against the shaft adjacent its outer edges in order to support the element 38, which regulates the cut of the tool. The reason for supportin the shaft adjacent its outer edges on these rib members is that these portions are more likely to be cylindrical in worn shafts than the portion of the shaft carrying the main thrust of the connecting rod.

. The grinding wheel 22, like the supporting member 38 is also of substantially the same diam- 4 eter as the width of the shaft surface 2'. For the first grinding operation the axis of the wheel is offset in a line perpendicular to the center line of the shaft bearing. In this position the grinding wheel will grind a major part of the bearing, leaving a ridge 48 and 48' (see Fig. 5) adjacent the sides of the bearing upon :which the rib members 46 and 46' are supported.

In order to grind these ridge members down to a point to conform with the first ground surface the wheel must be subsequently operated with its axis perpendicular to the center line of the hearing as shown in Figure 6.

To locate the grinding wheel eccentrically of the shaft, the supporting member 38 and the arm members 32 and 34 are so constructed as to support the center line of the shaft 2' slightly to one side the center line of the rectangular slot 28 and also to one side of a line extending through the axis of the drive shaft 28. This portion is shown in full lines in Figures 3 and 5. By reversing the member 38 within the slot 28, the center line of the shaft will be moved to the right as shown by the dotted line in Figure 3 and in line with the axis of the grinding wheel, as shown in Figure 6.

Adjustably receivable over the opposite or outer end of the wheel supporting tube member I6 is a sleeve or tube member 58, similar to the tube M. The tube 58 is held in adjusted position by the set screw 52. Adjacent the upper or outer end of the tube 58 is a pair of oppositely disposed hollow arm members 54 and 56. Fitted within the arm members are suitable pin members 58 and 68, which extend outwardly from the arm members and having their opposite ends pivotally supported in oppositely disposed arbors 62 and 64, which are in turn rigidly secured to the inner wall of the upper or outer guide member 14'. The pins 58 and 68 are rotatably supported within the arbors by screws 66 and 68 operating within the circumferential grooves 18 and 12 of the pin members. A key 16 prevents the sleeve members M and 58 from rotating upon the tube 16 and retains the axis of the pin members 58 and 68 parallel with the supporting arms 32 and 34 and likewise parallel with the center line of the connecting rod receiving portion of the crank shaft during the grinding operation.

The outer guide 14 comprises a cylindrical piston-like member adapted to slide within the cylinder similar to the operation of the engine piston. In order to use a single guide member for a number of different size cylinders, the guide member is provided with means for adjusting the guide to the various size cylinders. One form of the adjust ble guide is shown in Figures 3 and 4 and com rises a series of threaded studs 88, 88', 8|, 8|, 82, 82', 83 and 83' which may be extended outwardly beyond the outer surface of the guide M for varying its size. The guide 14 may also be adjusted laterally along the pins 58 and 68 by means of the screws 46 and 46' for grinding shaft bearing surfaces which are slightly offset.

A modified form of shaft positioning means is illustrated in Figures 10, 11 and 12 and comprises in particular a modified form of hinge member which may replace the hinge member 6 as shown and described in Figure 3. The modified member 86 is attached to the U-frame 4 and 4' as described for the member 6 and is provided with a rectangular slot 88 adjacent its upper surface similar to the slot 28 as shown in the member 6. Slidably fitted in the slot is a rectangular member 98 which is adjustable along a line parallel with the axis or the drive shaft and grinding wheel. To make these adjustments there is -a screw '92 extending through the base of the slot having a knurled head 93 and a retension spring 94, which is constructed and operated in substantially the same manner as that described for the adjusting screw 38 in Figure 3. Supported within a semi-cylindrical recessfifi in the upper surface of the member 86 is a support 95 for the connecting rod receiving portion of the crank shaft. The support 95 is also provided with flange members 81 and 39 and ribs GI and 93 for supporting the shaft in substantially the same manner as the bearing support 39 in Figure 3. The support is prevented from lateral movement by the threaded pin 93 operating within the slot '99. This arrangement is adapted to allow the shaft support to rock through a predetermined arc for allowing for the fi st and second grinding operation which has been previously described. For positioning the shaft portion 2 in relation to the grinding wheel 22 the roller is utilized as shown and described in Figure 3, except in this form the full thrust-of the rotating shaft is borne by the roller, whereas in the support shown in Figure 3 the major portion of the thrust is taken up by the support.

Figures 13 to 16 show a modified form of an adjustable guide member. The guide member comprises a cylindrical frame Edd having inwardly disposed rim members I86 and H18 extending around the upper and lower edges thereof respectively. Located adjacent the outer circumferential edge of the frame are a. plurality of eccentrically mounted cylinder members If, H12,

$03 and Hi l. These eccentric cylinders are pivoted within the upper and lower rim members and adjacent the outer edge thereof and are supported upon journals H8, Ill, H2, and H3 and journals H8, and H3. Secured to the top journa ls are arms H5, H8 by pins it!!! and I29. There is provided in the upper rimmember Hi6 semicircular slots I22 and i2 3 of approximately 170. Operating within the slots are bolts I24 and I26 carried by the outer ends of the arms on which..

are threaded nuts i2? and I28 respectively to provide fastening means for the eccentric members. To adjust these members the outer end of. the arm is moved along the slot and secured in its appropriate position by the above named fastening means. The bolt I24 is flattened at I30 as shown in Figure 16 to prevent it from turning when tightening the nut I21. The means for attaching the modified guide to the tool are substantially the same as described in Figure 3, the

pins 58 and 30 extending outwardly from the tube to engage arborsfib and on the frame of theguideand the tube member 50 being secured to the tubular drive shaft support I6 by means ,of a set screw, or other suitable means.

The tool is further provided with a pair of tension springs I29 and Edi which are adapted to urge the tool outwardly toward the outer end :of :the cylinder, keeping the shaft support forced against the shaft, theinner ends of the "springs The of the crankshaft throw.

by a stud I35 and nut I35 engaging the footI36' of the base into which the bar is adjustably secured in position by a, thumbscrew I38.

To place the tool in operation, the .tool is assembled as shown in Figure 3, the outer guide and the shaft positioning means for the connecting rod receiving portion of the shaft are fastened to the grinding wheel and drive shaft supporting tube I E in their approximate location. Thehin'ge member is released from one side of the U-frame by the screw Ill. The tool is then inserted into and through the cylinder Ml] as shown in Figure :1. The crank shaft is then inserted between the U-frame member 4 and Li and the hinge member is fastened in place with the bearing support 30 in its offset position as shown in full lines in Figure .3 for the first grinding operation. While in'this position the roller 25 is moved in contact with the shaft '2' .and fastened by the screw '29. At this point in the preparation the grinding wheel should be slightly above the upper surface of the .crank shaft. The spring 53!) and It" are fastened between the pins 58 and 60 and the bracket I34 bringing and retaining the support .30 in contact with theshaft. To begin the grinding, the grinding wheel 22 is set in motion in the direction as indicated by the arrow in Figure 3.

The wheel is then brought in contact with the shaft by moving the supportad outwardly in the slot by operating the screw 38. As the wheel is brought in contact with the shaft the crank shaft is slowly rotated in the direction of the arrows as indicated on the shaft in Figure 3. The shaft is rotated by .a separate electric motor or other suitable means at a comparatively slow rate of speed.

As the tool is carried around the crank shaft throw :the guide moves within the cylinder .in substantially the same manner in which the piston operates, the outer end of the grinding wheel supporting member It being pivotably connected'with the guide member ata predetermined point within the cylinder area. Subsequent cuts are made by the grinding wheel as the supporting member 39 is further advanced upwardly within the slot. After the bearing has been ground to a predetermined diameter while in its offset position there remains the outer portions of the bearing 48 and 48' to be ground to the level of .the first ground portion. To accomplish this the roller 25 is released by the screw 29 and moved back to the point indicated by the dotted line 2", where it is again fastened in place. The hinge member is again lowered and the support '30 is reversed within the slot 28 and at the same time lowered to a point adjacent the bottom of the slot 28. The hinge is then tightened in place, the shaft portion 2 will then take the position as indicated by the dotted line 2". The grinding wheel axis is then in a position perpendicular to the center line of the shaft. The second grinding operation may now be carried out in substantially the same manner as the first grinding operation. When the second grinding operation is completed the shaft will appear as in Figure l and will be of the same diameter throughout its entire surface.

It will be noted that during both the first and second grinding operation, that the springs I3! maintain the tool in contact with the bottom In case the throw is non-circular due 'to wear, as is usually the case, there will be some positions of the crankshaft where a given setting of the micrometer adjust- :ment screw 39 will leave the grinding when out of contact with the crank throw. By providing the springs l3l to constantly bias the tool upwardly, the grinding face is thus maintained at a predetermined distance from the lower face of the crankshaft throw along its edges.

The form of the invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings or described in this specification as various changes in the details of construction may be resorted to without departing from the spirit of the invention. Only in so far as the invention has been particularly pointed out in the accompanying claims is the same to be limited.

I claim: 1. A crank shaft grinding tool adapted to be inserted within a cylinder of an engine having a crank shaft comprising, a grinding wheel and a drive shaft therefor, a positioning member at one end of said tool adapted to reciprocate within the cylinder and having means associated therewith for varying the size thereof and a positioning member at the opposite end of the said tool for engaging the crank shaft, means for urging the tool in the direction of the cylinder positioning means and means associated with the crank shaft positioning means for supporting the grinding wheel in proper grinding relationship with the crank-shaft as the said crank shaft is rotated in its supporting bearings.

2. A crank shaft grinding tool comprising an adjustable guide member adapted to be inserted within the cylinder of an engine having a crank shaft, a grinding wheel and a drive shaft therefor, means for pivotably supporting the said grinding wheel outwardly from one end of the said guide, a crank shaft positioning mean associated with the grinding wheel support and extending beyond the said grinding wheel, a crank shaft support carried by said crank shaft positioning means and adapted to be positioned on the opposite side of the said shaft from the wheel and means for adjusting the shaft support relative to the cutting surface of the said wheel.

3. A crank shaft grinding tool adapted to be inserted within a cylinder of an engine having a crank shaft comprising, a grinding wheel rotating in a plane parallel to a tangent to the surface of the crank shaft, a drive shaft for said grinding wheel, a supporting member for said drive shaft and grinding wheel, a crank shaft positioning member adjustably secured to the end of the drive shaft support adjacent the grinding wheel, and a cylinder positioning member secured to the outer portion of the said drive shaft support, the crank shaft positioning member extending around the crank shaft to support the crank shaft opposite the said grinding wheel, and means for adjusting the said support in a line parallel with the axis of the said grinding wheel and means for urging the tool in the direction of the cylinder positioning member.

4. A crank shaft throw bearing surface grind- ,ing tool adapted to be inserted within a cylinder of an engine having a crank shaft, comprising a grinding wheel and a drive shaft therefor, a supporting member for said drive shaft and grinding wheel, a crank shaft positioning member secured to the end of the drive shaft support adjacent the grinding wheel, said positioning member extending around the crank shaft to support the crank shaft opposite the grinding wheel, a support for receiving the said crank shaft bearing portion of substantially the same length as the said bearing portion, said support having means adjacent its outer edges for contacting and supporting the said shaft adjacent the outer edges of the bearing surface, means associated with the said crank shaft support for adjusting the said support in a line parallel with the axis of the said grinding wheel and relative to the said crank shaft positioning means and means for urging the tool in the direction of the said grinding wheel and against the crank shaft supporting means.

5. A power tool for grinding the throws of an engine crankshaft while positioned in the engine, comprising a member engageable with the shaft throw and having a bearing for a grinding wheel shaft extending perpendicularly to the crankshaft and on the side thereof toward the engine cylinder, a grinding wheel shaft mounted in the bearing and carrying a grinding wheel with its fiat end face tangent to the surface of the crankshaft throw, means extending into the engine cylinder for driving the grinding wheel shaft, and guide means movable along the cylinder Walls for preventing rotation of the tool as the crankshaft is rotated.

6. A power tool for grinding the throws of an engine crankshaft while positioned in the engine, comprising a member engageable with the shaft throw and having a bearing for a grinding wheel shaft extending perpendicularly to the crankshaft and on the side thereof toward the engine cylinder, a grinding wheel shaft mounted in the bearing and carrying a grinding wheel with its flat end face tangent to the surface of the crankshaft throw, means extending into the engine cylinder for driving the grinding wheel shaft, and means engaging the engine block forming a guide for the tool and arranged to permit sliding of the tool longitudinally of the cylinder axis and swinging in a plane perpendicular to the crankshaft axis but rigidly positioning the tool against movement angularly in the plane common to the cylinder and crankshaft axes.

7. A power tool for grinding the throws of an engine crankshaft while positioned in the engine, comprising a bearing for a grinding wheel shaft, a power driven shaft supported in said bearing and carrying a face-contact grinding wheel at its end, means for locating the face of the grinding wheel comprising a yoke attached to the bearing and engaging the crankshaft throw to position the wheel at an adjustable predetermined distance from the center of the throw and on the side toward the engine cylinder, said means also including a reciprocating and pivoting guide engaging the engine block to position the wheel axis against displacement angularly in the plane common to the crankshaft and cylinder axes.

8. A power tool for grinding the throws of an engine crankshaft while positioned in the engine, comprising a bearing for a grinding wheel shaft, motor driven means extending into the engine cylinder and terminating in said bearing, a facecontact grinding wheel driven thereby, means for locating the face of the grinding wheel comprising a yoke attached to the bearing and engaging the crankshaft throw to position the wheel at an adjustable predetermined distance from the center of the throw and on the side toward the engine cylinder, said means also including a reciprocating and pivoting guide engaging the engine block to position the wheel axis against displacement angularly in the plane common to the crankshaft and cylinder axes.

9, A power tool for grinding the throws of an 9 engine crankshaft while positioned in the engine, comprising a power driven grinding wheel, means contacting the crankshaft on only the side opposite the cylinder for positioning the wheel tangent to the crankshaft throw on the side 5 adjacent the cylinder, driving means extending into the cylinder for rotating the grinding wheel, and guide means engaging the engine block for locating the tool against angular displacement in the plane common to the crankshaft and 10 cylinder axes.

HARRY T. RUTHERFORD.

REFERENCES CITED The following references are of record in the 15 file of this patent:

Number Number 10 UNITED STATES PATENTS Name Date Goulden Nov. 24, 1936 Morris Mar. 21, 1939 Brazil Mar. 18, 1941 Hanson Mar. 10, 1942 Petersen Mar. 24, 1942 Sunnen Jan. 26, 1943 Emory Aug. 17, 1948 FOREIGN PATENTS Country Date Germany Nov. 28, 1912 Great Britain Apr. 16, 1934 

